Page 1164 of 3115
A21040
Reference (Bank 1 Sensor 1 System Drawing)
From
BatteryEFI or ECD
No. 1 FuseEFI or ECD
RelayEFI or ECD
No. 2 FuseHeater Oxygen
Sensor
Heater
SensorHT1A
OX1A
E2
MRELECM
- DIAGNOSTICSENGINE
DI-1 15
308 Author: Date:
2004 LAND CRUISER (RM1071U)
NG Repair or replace harness or connector.
OK
6 Check air induction system (See page SF-1).
CHECK:
Check the air induction system for vacuum leaks.
NG Repair or replace
air induction system.
OK
7 Check fuel pressure (See page SF-7).
CHECK:
Check the fuel pressure (high or low pressure).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
Page 1166 of 3115
- DIAGNOSTICSENGINE
DI-1 17
310 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0133 Oxygen Sensor Circuit Slow Response
(Bank 1 Sensor 1)
DTC P0153 Oxygen Sensor Circuit Slow Response
(Bank 2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0031 on page DI-49.
DTC No.DTC Detecting ConditionTrouble Area
P0133
P0153
After engine has been warmed up, if response time that heated
oxygen sensor's output voltage reaches from RICH to LEAN,
or from LEAN to RICH, is 0.6 seconds or more during idling.
(2 trip detection logic)Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Heated oxygen sensor heater
EFI or ECD relay
Ai i d ti tP0153If response time of heated oxygen sensor's output voltage in
one RICH-LEAN cycle is 5.6 seconds or more during idling.
(2 trip detection logic)Air induction system
Fuel pressure
Injector
ECM
HINT:
Bank 1 refers to bank that includes cylinder No. 1.
Bank 2 refers to bank that does not includes cylinder No. 1.
Sensor 1 refers to the sensor closer to the engine assembly.
DIC27-01
Page 1174 of 3115
A20870
E1 +B
OX
+BHT
OX E1HT H5
H7
H6
H8
Components Side:
Bank1 Sensor1, Bank2 Sensor1
Bank1 Sensor2, Bank2 Sensor2
A21543
1
23
4 EFI or ECD Relay
- DIAGNOSTICSENGINE
DI-125
318 Author: Date:
2004 LAND CRUISER (RM1071U)
3 Check resistance of heated oxygen sensor heater.
PREPARATION:
Disconnect the H5, H6, H7 or H8 heated oxygen sensor con-
nector.
CHECK:
Measure resistance between terminals of the heated oxygen
sensor.
OK:
Tester ConnectionSpecified Condition
HT (H5-1) - +B (H5-2)11 to 16 W (20°C)
HT (H6-1) - +B (H6-2)11 to 16 W (20°C)
HT (H7-1) - +B (H7-2)11 to 16 W (20°C)
HT (H8-1) - +B (H8-2)11 to 16 W (20°C)
NG Replace heated oxygen sensor.
OK
4 Check EFI or ECD relay.
PREPARATION:
Remove the EFI or ECD relay from the engine room R/B.
CHECK:
Inspect the EFI or ECD relay.
OK:
Terminal No.ConditionSpecified Condition
2 - 4ConstantContinuity
UsuallyNo Continuity
1 - 3Apply B+ between
terminals 2 and 4Continuity
NG Replace EFI or ECD relay.
OK
Page 1176 of 3115
A21040
Reference (Bank 1 Sensor 1 System Drawing)
From
BatteryEFI or ECD
No. 1 FuseEFI or ECD
RelayEFI or ECD
No. 2 FuseHeater Oxygen
Sensor
Heater
SensorHT1A
OX1A
E2
MRELECM
- DIAGNOSTICSENGINE
DI-127
320 Author: Date:
2004 LAND CRUISER (RM1071U)
NG Repair or replace harness or connector.
OK
6 Check air induction system (See page SF-1).
CHECK:
Check the air induction system for vacuum leaks.
NG Repair or replace air induction system.
OK
7 Check fuel pressure (See page SF-7).
CHECK:
Check the fuel pressure (high or low pressure).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
Page 1178 of 3115
- DIAGNOSTICSENGINE
DI-129
322 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0134 Oxygen Sensor Circuit No Activity Detected
(Bank 1 Sensor 1)
DTC P0154 Oxygen Sensor Circuit No Activity Detected
(Bank 2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0031 on page DI-49.
DTC No.DTC Detecting ConditionTrouble Area
P0134
P0154
After the engine is warmed up, heated oxygen sensor (bank 1,
sensor 1) output does not indicate RICH (more than 0.45 V)
even once when the following conditions continue for 65 sec.
or more:
(a) Engine speed: 1,400 rpm or more
(b) Vehicle speed: 25 to 81 mph (40 to 130 km/h) or more
(c) Throttle valve does not fully closed
(d) 180 sec. or more after starting engine
(e) Engine coolant temperature more than 40°C (104°F)
Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Heated oxygen sensor heater
EFI or ECD relay
Air induction system
Fuel pressure
PCV hose connection
PCV valve and hose
Injector
Gas leakage on exhaust system
PCV piping
ECM
HINT:
Bank 1 refers to bank that includes cylinder No. 1.
Bank 2 refers to bank that does not includes cylinder No. 1.
Sensor 1 refers to the sensor closer to the engine assembly.
After confirming DTC P0134 and P0154, check the output voltage of the heated oxygen sensor in the
"DIAGNOSIS / ENHANCE OBD II / DATA LIST / ALL" using the OBD II scan tool or the hand-held tester.
If output voltage of the heated oxygen sensor is always less than 0.1 V, heated oxygen sensor circuit
may be open or short.
MONITOR DESCRIPTION
The ECM uses the heated oxygen sensor to optimize the air-fuel mixture in closed-loop fuel control. This
control helps decrease exhaust emissions by providing the catalyst with a nearly stoichiometric mixture.
The sensor detects the oxygen level in the exhaust gas and the ECM uses this data to control the air-fuel
ratio. The sensor output voltage ranges from 0 V to 1 V. If the signal voltage is less than 0.4 V, the air-fuel
ratio is LEAN. If the signal voltage is more than 0.55 V, the air-fuel ratio is RICH. If the conditions for the
closed-loop fuel control are met and after a specified time-period, the sensor's output signal never indicates
RICH, the ECM will conclude that the closed-loop fuel control is malfunctioning. The ECM will illuminate the
MIL and a DTC is set.
DIC28-01
Page 1183 of 3115
A20870
E1 +B
OX
+BHT
OX E1HT H5
H7
H6
H8
Components Side:
Bank1 Sensor1, Bank2 Sensor1
Bank1 Sensor2, Bank2 Sensor2
A21543
1
23
4 EFI or ECD Relay
DI-134
- DIAGNOSTICSENGINE
327 Author: Date:
2004 LAND CRUISER (RM1071U)
4 Check resistance of heated oxygen sensor heater.
PREPARATION:
Disconnect the H5, H6, H7 or H8 heated oxygen sensor con-
nector.
CHECK:
Measure resistance between terminals of the heated oxygen
sensor.
OK:
Tester ConnectionSpecified Condition
HT (H5-1) - +B (H5-2)11 to 16 W (20°C)
HT (H6-1) - +B (H6-2)11 to 16 W (20°C)
HT (H7-1) - +B (H7-2)11 to 16 W (20°C)
HT (H8-1) - +B (H8-2)11 to 16 W (20°C)
NG Replace heated oxygen sensor.
OK
5 Check EFI or ECD relay.
PREPARATION:
Remove the EFI or ECD relay from the engine room R/B.
CHECK:
Inspect the EFI or ECD relay.
OK:
Terminal No.ConditionSpecified Condition
2 - 4ConstantContinuity
UsuallyNo Continuity
1 - 3Apply B+ between
terminals 2 and 4Continuity
NG Replace EFI or ECD relay.
OK
Page 1184 of 3115
A21339
E1 +B
OXHT
H5
H7
Components Side:
Bank1 Sensor1, Bank2 Sensor1
A21340
HT1A
OX1AE6
ECM ConnectorOX2A
HT2A
A21040
Reference (Bank 1 Sensor 1 System Drawing)
From
BatteryEFI or ECD
No. 1 FuseEFI or ECD
RelayEFI or ECD
No. 2 FuseHeater Oxygen
Sensor
Heater
SensorHT1A
OX1A
E2
MRELECM
- DIAGNOSTICSENGINE
DI-135
328 Author: Date:
2004 LAND CRUISER (RM1071U)
6 Check for open and short in harness and connector between ECM and heated
oxygen sensor (bank 1, 2 sensor 1).
PREPARATION:
(a) Disconnect the H5 or H7 heated oxygen sensor connec-
tor.
(b) Disconnect the E6 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
OX (H5-3) - OX1A (E6-23)Below 1 W
HT (H5-1) - HT1A (E6-4)Below 1 W
OX (H7-3) - OX2A (E6-22)Below 1 W
HT (H7-1) - HT2A (E6-33)Below 1 W
OX (H5-3) or OX1A (E6-23) -
Body ground10 kW or higher
HT (H5-1) or HT1A (E6-4) -
Body ground10 kW or higher
OX (H7-3) or OX2A (E6-22) -
Body ground10 kW or higher
HT (H7-1) or HT2A (E6-33) -
Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Page 1187 of 3115
DI-138
- DIAGNOSTICSENGINE
331 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0136 Oxygen Sensor Circuit Malfunction (Bank 1
Sensor 2)
DTC P0156 Oxygen Sensor Circuit Malfunction (Bank 2
Sensor 2)
CIRCUIT DESCRIPTION
Refer to DTC P0031 on page DI-49.
DTC No.DTC Detecting ConditionTrouble Area
P0136
P0156
The following condition (a) or (b) continues 300 sec. or more.
(a) During driving with the engine warmed up, heated oxygen
sensor output does not change.
(b) Heated oxygen sensor output is very low most of the time.Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Heated oxygen sensor heater
EFI or ECD relay
HINT:
Bank 1 refers to bank that includes cylinder No. 1.
Bank 2 refers to bank that does not includes cylinder No. 1.
Sensor 2 refers to the sensor farther away from the engine assembly.
MONITOR DESCRIPTION
The ECM monitors the rear heated oxygen sensor in the following 3 items:
(1) If the rear heated oxygen sensor voltage changes between Rich and Lean while the vehicle is
running (repeating acceleration and deceleration). If not, the ECM interprets this as a malfunc-
tion, illuminates the MIL, and then sets DTC.
(2) If the rear heated oxygen sensor voltage does not remain at less than 0.05 V for a long time while
the vehicle is running. If not, the ECM interprets this as a malfunction, illuminates the MIL, and
then sets DTC.
(3) If the sensor's voltage drops to below 0.2 V (extremely Lean status) immediately when the ve-
hicle decelerates and the fuel cut is working. if not, the ECM interprets this to mean the sensor's
response feature has deteriorated, illuminates the MIL, and then sets DTC.
DIC29-01
